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How Does an Electric Motor Work? A Quick Overview

Have you ever wondered how an electric motor works? These workhorses power countless appliances throughout your building, from washers and dryers to massive pumps essential to building operations. Discover the fascinating engineering and principles of electric motors and how they convert electricity into torque within various building pumps.

How Does an Electric Motor Work?

The Core Principles

An electric pump moves liquids by combining electromagnetism and fluid mechanics. At its heart, the electric motor generates the force that drives the pump by using electricity to create a magnetic field.

The motor comprises two main components: a stationary part, called a stator, and a rotating part, called a rotor. Each plays a crucial role in converting electrical energy into rotational force. The stator houses permanent magnets or electromagnets, and the rotor has wire coils. As electricity passes through the coils, it creates a magnetic field in the rotor.

The interaction between the magnetic fields of the stator and rotor creates repulsion and attraction, causing the rotor to spin continuously. The rotation transfers energy to the pump mechanism, a shaft or impeller, creating movement within the pump.

Movement equates to a pressure differential. On the inlet side of the pump, the movement creates a low-pressure zone, drawing liquid in. On the outlet side of the pump, the movement creates a high-pressure zone, pushing liquid out.

The Stator

One of the essential components of how an electric motor works, the stator is the stationary outer shell of the motor that houses the electromagnetic field. Its construction typically includes laminated steel sheets that reduce energy losses from eddy currents (unwanted electrical currents within a conductor).

There are two main types of stator: permanent magnet stator and electromagnet stator. A permanent magnet stator uses several magnets strategically placed within the stator to generate a constant magnetic field.

An electromagnet stator uses coils of wire wrapped around a steel core to generate a magnetic field with electricity. This type of stator allows for greater control and dependability.

The Rotor

The rotor is the inner, rotating shaft of the motor, responsible for generating the mechanical output. A rotor consists of two primary parts: the shaft and rotor core. The shaft is the central axle that provides a point of attachment for the load (the device the motor needs to turn) and transmits the rotational force.

The rotor core is vital to how an electric motor works. It is made of laminated steel sheets and houses the conductor that interacts with the stator’s magnetic field.

As with stators, there are two main types:

1. Wound rotor: This type of rotor has wires wrapped around the core. When electrical current passes through the coils, it interacts with the stator’s field to create torque. This rotor type is common in AC motors for applications requiring variable speeds.
2. Squirrel cage rotor: This rotor is a simpler design comprising conducting bars arranged in a cage-like structure around the rotor core. As electrical current passes through the bars, the rotor interacts with the stator’s field, creating torque. Squirrel cages are standard in AC induction motors.

In DC motors, a commutator is necessary. It is a cylindrical device with segmented metal contacts. The device reverses the current direction in the rotor coils to ensure continuous rotation.

Rotation

Knowing how an electric motor works involves understanding how force translates to continuous rotation. This seemingly simple feat relies on the clever interplay between magnetism and electrical design.

The magnetic repulsion and attraction generated by the interplay between the stator’s and rotor’s magnetic fields act tangentially to the rotor’s axis, constantly pushing and pulling it around. Motors have multiple magnetic poles in the stator and rotor, creating numerous points of attraction and repulsion. This creates a consistent and smooth turning force rather than a jerking motion when poles first interact.

In AC motors, the coils in the stator use the alternating current to create a rotating magnetic field. The rotating field then “drags” the rotor’s magnetic field along, causing it to spin continuously in the same direction as the stator’s field.

In DC motors, the commutator is the key to continuous rotation. The device effectively swaps the polarity of the rotor’s magnetic field to ensure a constant rotational force.

How Do Electric Motors Work and Contribute to Property Infrastructure?

Building Pumps

Electric motors play a vital role in the unseen infrastructure of your building. They are the driving force behind various pumps that ensure proper water management and fire safety. Sump pumps, water booster pumps, and fire pumps are three critical devices that use electric motors to ensure buildings function smoothly and safely.

Sump Pumps

Sump pumps are workhorses that reside in basements and crawlspaces. They use a submersible electric motor encased in a sealed housing. When water levels rise from heavy rains or flooding, a float switch in the pump activates the motor, powering the pump and drawing water away from the property.

Water Booster Pumps

In a multi-story residential property, booster pumps ensure stable water pressure throughout the building. These pumps use electric motors to increase water pressure from the main supply line.

Fire Safety Systems

Fire pumps are crucial components of fire safety and suppression systems. The pumps feature heavy-duty electric motors. When a fire alarm triggers the pump, the motor activates, driving the pump to deliver pressurized water to the building’s sprinkler system. The reliable, high-powered motor ensures a high-volume and steady water supply is readily available to fight fires and save lives.

Antler Pumps Can Help With How Electric Motors Work

Annual Contracts and Optimal Pump Performance

Like any machine, electric motors, especially in pumps, require regular maintenance for optimum functionality. Routine checkups ensure smooth operation and prevent potential leaks, decreased pressure, and motor burnout, saving you from unexpected disruptions and water damage.

Contact Antler Pumps at 212-534-2500 to schedule an inspection with a qualified technician who understands the intricacies of how an electric motor works in a pump and how to keep them operating. Also, ask about our annual service contracts to ensure you never miss scheduled maintenance checks.